Messages in this thread | | | From | "Kani, Toshimitsu" <> | Subject | Re: [PATCH v2 4/7] ghes_edac: avoid multiple calls to dmi_walk() | Date | Mon, 14 Aug 2017 17:52:25 +0000 |
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On Mon, 2017-08-14 at 19:05 +0200, Borislav Petkov wrote: > On Mon, Aug 14, 2017 at 04:48:57PM +0000, Kani, Toshimitsu wrote: > > Right, but the issue is how [ghes_edac_]report_mem_error() protects > > from possible concurrent calls from multiple GHES sources when > > there is only a single mci. > > Do you know of an actual firmware reporting multiple errors > concurrently?
I do not know. We have multiple GHES entries, but they all use SCI. Since ACPICA uses a single threaded workqueue for notify handlers, they are serialized among SCIs.
ACPI 6.2 defines multiple notification types in Table 18-383, and ghes_proc() can be called from ghes_poll_func(), ghes_irq_func(), and ghes_notify_sci(). So, I think it is safe to operate per an entry basis.
> GHES v2 even needs to ACK the current error first before it can read > the next one.
Yes, but this ACK is done per a GHES entry as well.
Thanks, -Toshi
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